420SEL (126.035) V8-4.2L (116.965) (1986)
10
Extraction pipe
NOTE: Transition fault during the warming-up phase on vehicles with KA injection system can be caused by coked-up inlet valves.
The inlet valves can be cleaned with a sandblasting device without removing the intake manifold.
Cleaning Procedure:
Walnut shell granulate under high pressure is blasted on the disks of the closed inlet valves via the mounting bores of the injection valves. At the same
time, the carbon residue is extracted together with the granulate via the throttle valve pipe into the sand-blasting unit.
The valve disk is partly obstructed by the valve stem. In order to clean the obstructed part the valve must be turned once by 180°.
Maintenance and Filling of Sandblasting Device: